xref: /openbmc/u-boot/drivers/ddr/microchip/ddr2.c (revision e9c847c3)
1 /*
2  * (c) 2015 Paul Thacker <paul.thacker@microchip.com>
3  *
4  * SPDX-License-Identifier:	GPL-2.0+
5  *
6  */
7 #include <common.h>
8 #include <wait_bit.h>
9 #include <linux/kernel.h>
10 #include <linux/bitops.h>
11 #include <mach/pic32.h>
12 #include <mach/ddr.h>
13 
14 #include "ddr2_regs.h"
15 #include "ddr2_timing.h"
16 
17 /* init DDR2 Phy */
18 void ddr2_phy_init(void)
19 {
20 	struct ddr2_phy_regs *ddr2_phy;
21 	u32 pad_ctl;
22 
23 	ddr2_phy = ioremap(PIC32_DDR2P_BASE, sizeof(*ddr2_phy));
24 
25 	/* PHY_DLL_RECALIB */
26 	writel(DELAY_START_VAL(3) | DISABLE_RECALIB(0) |
27 	       RECALIB_CNT(0x10), &ddr2_phy->dll_recalib);
28 
29 	/* PHY_PAD_CTRL */
30 	pad_ctl = ODT_SEL | ODT_EN | DRIVE_SEL(0) |
31 		  ODT_PULLDOWN(2) | ODT_PULLUP(3) |
32 		  EXTRA_OEN_CLK(0) | NOEXT_DLL |
33 		  DLR_DFT_WRCMD | HALF_RATE |
34 		  DRVSTR_PFET(0xe) | DRVSTR_NFET(0xe) |
35 		  RCVR_EN | PREAMBLE_DLY(2);
36 	writel(pad_ctl, &ddr2_phy->pad_ctrl);
37 
38 	/* SCL_CONFIG_0 */
39 	writel(SCL_BURST8 | SCL_DDR_CONNECTED | SCL_RCAS_LAT(RL) |
40 	       SCL_ODTCSWW, &ddr2_phy->scl_config_1);
41 
42 	/* SCL_CONFIG_1 */
43 	writel(SCL_CSEN | SCL_WCAS_LAT(WL), &ddr2_phy->scl_config_2);
44 
45 	/* SCL_LAT */
46 	writel(SCL_CAPCLKDLY(3) | SCL_DDRCLKDLY(4), &ddr2_phy->scl_latency);
47 }
48 
49 /* start phy self calibration logic */
50 static int ddr2_phy_calib_start(void)
51 {
52 	struct ddr2_phy_regs *ddr2_phy;
53 
54 	ddr2_phy = ioremap(PIC32_DDR2P_BASE, sizeof(*ddr2_phy));
55 
56 	/* DDR Phy SCL Start */
57 	writel(SCL_START | SCL_EN, &ddr2_phy->scl_start);
58 
59 	/* Wait for SCL for data byte to pass */
60 	return wait_for_bit(__func__, &ddr2_phy->scl_start, SCL_LUBPASS,
61 			    true, CONFIG_SYS_HZ, false);
62 }
63 
64 /* DDR2 Controller initialization */
65 
66 /* Target Agent Arbiter */
67 static void ddr_set_arbiter(struct ddr2_ctrl_regs *ctrl,
68 			    const struct ddr2_arbiter_params *const param)
69 {
70 	int i;
71 
72 	for (i = 0; i < NUM_AGENTS; i++) {
73 		/* set min burst size */
74 		writel(i * MIN_LIM_WIDTH, &ctrl->tsel);
75 		writel(param->min_limit, &ctrl->minlim);
76 
77 		/* set request period (4 * req_period clocks) */
78 		writel(i * RQST_PERIOD_WIDTH, &ctrl->tsel);
79 		writel(param->req_period, &ctrl->reqprd);
80 
81 		/* set number of burst accepted */
82 		writel(i * MIN_CMDACPT_WIDTH, &ctrl->tsel);
83 		writel(param->min_cmd_acpt, &ctrl->mincmd);
84 	}
85 }
86 
87 const struct ddr2_arbiter_params *__weak board_get_ddr_arbiter_params(void)
88 {
89 	/* default arbiter parameters */
90 	static const struct ddr2_arbiter_params arb_params[] = {
91 		{ .min_limit = 0x1f, .req_period = 0xff, .min_cmd_acpt = 0x04,},
92 		{ .min_limit = 0x1f, .req_period = 0xff, .min_cmd_acpt = 0x10,},
93 		{ .min_limit = 0x1f, .req_period = 0xff, .min_cmd_acpt = 0x10,},
94 		{ .min_limit = 0x04, .req_period = 0xff, .min_cmd_acpt = 0x04,},
95 		{ .min_limit = 0x04, .req_period = 0xff, .min_cmd_acpt = 0x04,},
96 	};
97 
98 	return &arb_params[0];
99 }
100 
101 static void host_load_cmd(struct ddr2_ctrl_regs *ctrl, u32 cmd_idx,
102 			  u32 hostcmd2, u32 hostcmd1, u32 delay)
103 {
104 	u32 hc_delay;
105 
106 	hc_delay = max_t(u32, DIV_ROUND_UP(delay, T_CK), 2) - 2;
107 	writel(hostcmd1, &ctrl->cmd10[cmd_idx]);
108 	writel((hostcmd2 & 0x7ff) | (hc_delay << 11), &ctrl->cmd20[cmd_idx]);
109 }
110 
111 /* init DDR2 Controller */
112 void ddr2_ctrl_init(void)
113 {
114 	u32 wr2prech, rd2prech, wr2rd, wr2rd_cs;
115 	u32 ras2ras, ras2cas, prech2ras, temp;
116 	const struct ddr2_arbiter_params *arb_params;
117 	struct ddr2_ctrl_regs *ctrl;
118 
119 	ctrl = ioremap(PIC32_DDR2C_BASE, sizeof(*ctrl));
120 
121 	/* PIC32 DDR2 controller always work in HALF_RATE */
122 	writel(HALF_RATE_MODE, &ctrl->memwidth);
123 
124 	/* Set arbiter configuration per target */
125 	arb_params = board_get_ddr_arbiter_params();
126 	ddr_set_arbiter(ctrl, arb_params);
127 
128 	/* Address Configuration, model {CS, ROW, BA, COL} */
129 	writel((ROW_ADDR_RSHIFT | (BA_RSHFT << 8) | (CS_ADDR_RSHIFT << 16) |
130 	       (COL_HI_RSHFT << 24) | (SB_PRI << 29)  |
131 	       (EN_AUTO_PRECH << 30)), &ctrl->memcfg0);
132 
133 	writel(ROW_ADDR_MASK, &ctrl->memcfg1);
134 	writel(COL_HI_MASK, &ctrl->memcfg2);
135 	writel(COL_LO_MASK, &ctrl->memcfg3);
136 	writel(BA_MASK | (CS_ADDR_MASK << 8), &ctrl->memcfg4);
137 
138 	/* Refresh Config */
139 	writel(REFCNT_CLK(DIV_ROUND_UP(T_RFI, T_CK_CTRL) - 2) |
140 	       REFDLY_CLK(DIV_ROUND_UP(T_RFC_MIN, T_CK_CTRL) - 2) |
141 	       MAX_PEND_REF(7),
142 	       &ctrl->refcfg);
143 
144 	/* Power Config */
145 	writel(ECC_EN(0) | ERR_CORR_EN(0) | EN_AUTO_PWR_DN(0) |
146 	       EN_AUTO_SELF_REF(3) | PWR_DN_DLY(8) |
147 	       SELF_REF_DLY(17) | PRECH_PWR_DN_ONLY(0),
148 	       &ctrl->pwrcfg);
149 
150 	/* Delay Config */
151 	wr2rd = max_t(u32, DIV_ROUND_UP(T_WTR, T_CK_CTRL),
152 		      DIV_ROUND_UP(T_WTR_TCK, 2)) + WL + BL;
153 	wr2rd_cs = max_t(u32, wr2rd - 1, 3);
154 	wr2prech = DIV_ROUND_UP(T_WR, T_CK_CTRL) + WL + BL;
155 	rd2prech = max_t(u32, DIV_ROUND_UP(T_RTP, T_CK_CTRL),
156 			 DIV_ROUND_UP(T_RTP_TCK, 2)) + BL - 2;
157 	ras2ras = max_t(u32, DIV_ROUND_UP(T_RRD, T_CK_CTRL),
158 			DIV_ROUND_UP(T_RRD_TCK, 2)) - 1;
159 	ras2cas = DIV_ROUND_UP(T_RCD, T_CK_CTRL) - 1;
160 	prech2ras = DIV_ROUND_UP(T_RP, T_CK_CTRL) - 1;
161 
162 	writel(((wr2rd & 0x0f) |
163 	       ((wr2rd_cs & 0x0f) << 4) |
164 	       ((BL - 1) << 8) |
165 	       (BL << 12) |
166 	       ((BL - 1) << 16) |
167 	       ((BL - 1) << 20) |
168 	       ((BL + 2) << 24) |
169 	       ((RL - WL + 3) << 28)), &ctrl->dlycfg0);
170 
171 	writel(((T_CKE_TCK - 1) |
172 	       (((DIV_ROUND_UP(T_DLLK, 2) - 2) & 0xff) << 8) |
173 	       ((T_CKE_TCK - 1) << 16) |
174 	       ((max_t(u32, T_XP_TCK, T_CKE_TCK) - 1) << 20) |
175 	       ((wr2prech >> 4) << 26) |
176 	       ((wr2rd >> 4) << 27) |
177 	       ((wr2rd_cs >> 4) << 28) |
178 	       (((RL + 5) >> 4) << 29) |
179 	       ((DIV_ROUND_UP(T_DLLK, 2) >> 8) << 30)), &ctrl->dlycfg1);
180 
181 	writel((DIV_ROUND_UP(T_RP, T_CK_CTRL) |
182 	       (rd2prech << 8) |
183 	       ((wr2prech & 0x0f) << 12) |
184 	       (ras2ras << 16) |
185 	       (ras2cas << 20) |
186 	       (prech2ras << 24) |
187 	       ((RL + 3) << 28)), &ctrl->dlycfg2);
188 
189 	writel(((DIV_ROUND_UP(T_RAS_MIN, T_CK_CTRL) - 1) |
190 	       ((DIV_ROUND_UP(T_RC, T_CK_CTRL) - 1) << 8) |
191 	       ((DIV_ROUND_UP(T_FAW, T_CK_CTRL) - 1) << 16)),
192 	       &ctrl->dlycfg3);
193 
194 	/* ODT Config */
195 	writel(0x0, &ctrl->odtcfg);
196 	writel(BIT(16), &ctrl->odtencfg);
197 	writel(ODTRDLY(RL - 3) | ODTWDLY(WL - 3) | ODTRLEN(2) | ODTWLEN(3),
198 	       &ctrl->odtcfg);
199 
200 	/* Transfer Configuration */
201 	writel(NXTDATRQDLY(2) | NXDATAVDLY(4) | RDATENDLY(2) |
202 	       MAX_BURST(3) | (7 << 28) | BIG_ENDIAN(0),
203 	       &ctrl->xfercfg);
204 
205 	/* DRAM Initialization */
206 	/* CKE high after reset and wait 400 nsec */
207 	host_load_cmd(ctrl, 0, 0, IDLE_NOP, 400000);
208 
209 	/* issue precharge all command */
210 	host_load_cmd(ctrl, 1, 0x04, PRECH_ALL_CMD, T_RP + T_CK);
211 
212 	/* initialize EMR2 */
213 	host_load_cmd(ctrl, 2, 0x200, LOAD_MODE_CMD, T_MRD_TCK * T_CK);
214 
215 	/* initialize EMR3 */
216 	host_load_cmd(ctrl, 3, 0x300, LOAD_MODE_CMD, T_MRD_TCK * T_CK);
217 
218 	/*
219 	 * RDQS disable, DQSB enable, OCD exit, 150 ohm termination,
220 	 * AL=0, DLL enable
221 	 */
222 	host_load_cmd(ctrl, 4, 0x100,
223 		      LOAD_MODE_CMD | (0x40 << 24), T_MRD_TCK * T_CK);
224 	/*
225 	 * PD fast exit, WR REC = T_WR in clocks -1,
226 	 * DLL reset, CAS = RL, burst = 4
227 	 */
228 	temp = ((DIV_ROUND_UP(T_WR, T_CK) - 1) << 1) | 1;
229 	host_load_cmd(ctrl, 5, temp, LOAD_MODE_CMD | (RL << 28) | (2 << 24),
230 		      T_MRD_TCK * T_CK);
231 
232 	/* issue precharge all command */
233 	host_load_cmd(ctrl, 6, 4, PRECH_ALL_CMD, T_RP + T_CK);
234 
235 	/* issue refresh command */
236 	host_load_cmd(ctrl, 7, 0, REF_CMD, T_RFC_MIN);
237 
238 	/* issue refresh command */
239 	host_load_cmd(ctrl, 8, 0, REF_CMD, T_RFC_MIN);
240 
241 	/* Mode register programming as before without DLL reset */
242 	host_load_cmd(ctrl, 9, temp, LOAD_MODE_CMD | (RL << 28) | (3 << 24),
243 		      T_MRD_TCK * T_CK);
244 
245 	/* extended mode register same as before with OCD default */
246 	host_load_cmd(ctrl, 10, 0x103, LOAD_MODE_CMD | (0xc << 24),
247 		      T_MRD_TCK * T_CK);
248 
249 	/* extended mode register same as before with OCD exit */
250 	host_load_cmd(ctrl, 11, 0x100, LOAD_MODE_CMD | (0x4 << 28),
251 		      140 * T_CK);
252 
253 	writel(CMD_VALID | NUMHOSTCMD(11), &ctrl->cmdissue);
254 
255 	/* start memory initialization */
256 	writel(INIT_START, &ctrl->memcon);
257 
258 	/* wait for all host cmds to be transmitted */
259 	wait_for_bit(__func__, &ctrl->cmdissue, CMD_VALID, false,
260 		     CONFIG_SYS_HZ, false);
261 
262 	/* inform all cmds issued, ready for normal operation */
263 	writel(INIT_START | INIT_DONE, &ctrl->memcon);
264 
265 	/* perform phy caliberation */
266 	if (ddr2_phy_calib_start())
267 		printf("ddr2: phy calib failed\n");
268 }
269 
270 phys_size_t ddr2_calculate_size(void)
271 {
272 	u32 temp;
273 
274 	temp = 1 << (COL_BITS + BA_BITS + ROW_BITS);
275 	/* 16-bit data width between controller and DIMM */
276 	temp = temp * CS_BITS * (16 / 8);
277 	return (phys_size_t)temp;
278 }
279